/*
 * Copyright 2002-2012 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.beans.factory.support;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;

import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.core.io.AbstractResource;
import org.springframework.util.Assert;

/**
 * Descriptive {@link org.springframework.core.io.Resource} wrapper for
 * a {@link org.springframework.beans.factory.config.BeanDefinition}.
 *
 * @author Juergen Hoeller
 * @see org.springframework.core.io.DescriptiveResource
 * @since 2.5.2
 */
class BeanDefinitionResource extends AbstractResource {

    private final BeanDefinition beanDefinition;


    /**
     * Create a new BeanDefinitionResource.
     *
     * @param beanDefinition the BeanDefinition objectto wrap
     */
    public BeanDefinitionResource(BeanDefinition beanDefinition) {
        Assert.notNull(beanDefinition, "BeanDefinition must not be null");
        this.beanDefinition = beanDefinition;
    }

    /**
     * Return the wrapped BeanDefinition object.
     */
    public final BeanDefinition getBeanDefinition() {
        return this.beanDefinition;
    }


    @Override
    public boolean exists() {
        return false;
    }

    @Override
    public boolean isReadable() {
        return false;
    }

    @Override
    public InputStream getInputStream() throws IOException {
        throw new FileNotFoundException(
                "Resource cannot be opened because it points to " + getDescription());
    }

    @Override
    public String getDescription() {
        return "BeanDefinition defined in " + this.beanDefinition.getResourceDescription();
    }


    /**
     * This implementation compares the underlying BeanDefinition.
     */
    @Override
    public boolean equals(Object obj) {
        return (obj == this ||
                (obj instanceof BeanDefinitionResource &&
                        ((BeanDefinitionResource) obj).beanDefinition.equals(this.beanDefinition)));
    }

    /**
     * This implementation returns the hash code of the underlying BeanDefinition.
     */
    @Override
    public int hashCode() {
        return this.beanDefinition.hashCode();
    }

}
